Pope Sergius III was Pope from 29 January 904 to his death in 911. He was pope during a period of feudal violence and disorder in central Italy, when warring aristocratic factions sought to use the material and military resources of the Papacy.

Because Sergius III had reputedly ordered the murder of his two immediate predecessors, Leo V and Christopher, and was the only pope to have allegedly fathered an illegitimate son who later became pope (John XI), his pontificate has been variously described as "dismal and disgraceful", and "efficient and ruthless".